The present invention relates to exercise machines, and more particularly to machines for simultaneously exercising both arms and both legs in a natural rhythmic skiing motion.
Certain devices or machines in the prior art provide the ability to exercise with motions similar to the present invention. However, these machines suffer from various disadvantages which are overcome by the present improved exercise machine. Such prior devices are shown in U.S. Pat. No. 4,618,139, which was issued to applicant on Oct. 21, 1986, and U.S. Pat. No. 4,529,194, which was issued to applicant on July 16, 1985.
Other known but more primitive exercise machines that exercise both the arms and legs include those disclosed in U.S. Pat. Nos. 4,512,571, 4,434,981, 4,023,795, and 2,772,881. Prior exercise machines that only exercise the legs are disclosed in U.S. Pat. Nos. 4,402,506, 4,406,451, 4,342,452, 3,659,842, 3,582,069, 1,982,843, and U.K. Patent Application GB No. 2,007,987. Additional exercise machines which apparently only exercise the individual's arms are disclosed in U.S. Pat. Nos. 2,921,791 and 518,967.
All of the identified prior art devices provide a limited degree of safe, smooth and comfortable exercise for the arms and legs, legs alone, or arms alone. However, none of the prior patents disclose exercise machines that readily accommodate the varying height, weight and fitness levels of individual users.
There is a need for a comfortable exercise machine that provides no jarring impact on knees and back while yet permitting independent and adjustable arm and leg movement resistances or exertion levels. It is also desirable that the chance of injury with such an exercise machine either be eliminated or substantially reduced.